Causes and effects of noise in landscape dynamics
Geomorphology, the study of landscape form and change, is at a crossroad. Quantification of patterns on Earth's surface has revealed surprising and robust order. Transport equations rooted in physics that relate material flux of sediment to environmental drivers have been derived and are capable of simulating realistic-looking topography [Dietrich et al., 2003]. Yet despite this rapid progress and an explosion of interest in the field, scientists are unable to predict sediment transport rates in rivers to better than an order of magnitude—they can only qualitatively anticipate the response of landscapes to land use or climatic changes. In addition, some argue that the sedimentary archive of landscape evolution is dominated by randomness [Sadler and Strauss, 1990], calling into question researchers' ability to reconstruct environmental change from the rock record.
I thank all of my mentors, graduate students, and colleagues, too numerous to mention here, for their continued enthusiasm and inspiration related to these ideas. I also thank the organizers, officers, and executive committee of the vibrant and growing Earth and Planetary Surface Processes Focus Group, for helping to build an inclusive community of landscape enthusiasts at AGU. Constructive comments from three anonymous reviewers improved the clarity and scope of the paper.